Method of preparing selenyl aryl thiazoles



Patented Dec. 19, 193? p H a H I UNITED STATES PATENT-cri ics METHOD OF PREPARING SELENYL Anvil THIAZOLES Lawrence R. Sperberg, Habana, Cubapassignor to Wingfoot Corporation, Wilmington, l )el., a corporation of Delaware No Drawing. Application August 23', 1938, Serial No. 226,304

10 Claims. (Cl. 260-304) This invention relates to a method of prepar- 36.2%. *Calculzited for CqHNSSe: S, 14.94. ing selenium compounds and, more particularly, Se, 36.9%. The product, therefore, is'presumed to a method of preparing selenyl aryl thiazoles. to have the formula v The mercaptobenzothiazoles are well known 5 compounds for which methods of preparation N 5 have been thoroughly worked out but the correa 3 20 s eH spondmg selenium compounds, in WhlCh selenium replaces sulfur in the mercapto group, are not so 6 well known and methods for their preparation 7 10 are not so well established. The present inven- Selenium can be introduced by means of any 10 til-711 aims to Provide a method for e p ep of a number of selenides, such as the normal seletion of these compounds in satisfactory yields nides, the hydro selenides and the poly selenides, and of adequate purity. The method consists in particularly, sodium selenide, sodium hydroreacting a selenide with a halogen-substituted selenide, and sodium poly selenide. In general, aryl thiazole to yie d the par cu ar compound the alkali metal selenides will be found to be the 15 desired. The reaction may be carried on in water most available and, of these, the normal selenides or other appropriate solvent and heat is usually are preferred. required. However, the temperature is not criti- The reaction is applicable to the preparation cal and reaction may ensue at temperatures from of other selenyl thiazoles, particularly the 2- that of the room, about D to about selenyl aryl thiazoles, such as 2-selenyl benzo- 100 C. or even higher. Equivalent or molecular thiazole, the preparation of which has been de- D D S are Ordinarily provided but an scribed above. Such compounds are generally cess of one reactant or the other may be presincluded by the formula ent. The reaction is preferably carried on under a reflux condenser and non-oxidizing conditions I 25 are desirable since the product oxidizes rather readily. Such conditions may be maintained by flushing out the apparatus with hydrogen before the run is started and then passing a small stream of hydrogen therethrough during the reaction. Wherel? there 15 attached to the bonds: of

To illustrate the process, the following exthe adJaset ajtoms of the P F ample is given, but it will be understood that the hydrogen ahphatlc aromailc invention is not limited to the condition stated Preferab1y= however these two adlajcent carbon and t Various modifi ati n may be made atoms form part of an arylene radical, such as therein phenylene, nitro phenylene, and naphthalene 35 EmmpZe radicals. Among such compounds may be mentioned 2-selenol 6-nitro benzothiazole, 2-se1eno1 Sodium hydro e en wa first prepared by alpha naphthothiazole, 2-selenol G-tertiary butyl solv g 13 grams 11101) of Sodium hydroxide benzothiazole, 4-5-dimethyl 2-selenol thiazole,

i 800 Of Water and sa u With hydrogen Z-selenol G-tertiary amyl benzothiazole, l-phenyl 4o selenide- An additional 18 grams f s m hy- 2-se1enol thiazole, 2-selenol 6-oxy phenyl benzodroxide in 200 cc. of water was then added to thiazole, 4-5-di p-anisyl 2-selenolthiazole, 4-5- form the normal sodium selenide. This was rediphenyl 2-se1enol thiazole, 2-se1enol 5-nitro acted with 68 grams (.40 mol) of chlor benzobenzothiazole, 5-6 or Z-methyl 2-selenol benzo- 45 thiazole added through a reflux condenser and thiazoles, 2-selenol 5- or 6-chlor benzothiazole, 5 the temperature was then raised to 98 C. very 5-6- or 7-hydroxy 2-selenol benzothiazoles, rapidly. After about a half hour all of the chlor 2-se1eno1 5- or G-aminobenzothiazole, 2-selenol benzothiazole had gone into solution and further AR-tetrahydro alpha naphthyl thiazone, etc. heating did not appear to increase the yields or The process may be applied to the preparation to cause any other change in the solution. The of the foregoing and other selenol aryl thiazoles 50 product was precipitated with dilute hydroby treating the corresponding halogen aryl thiachloric acid and purified by reprecipitating from zole with one of the selenides mentioned above. caustic twice. The precipitate was filtered with The halogen substituent may be chlorine or brosuction and allowed to dry, a quantitative yield mine or one of the other halogens, but is usually being obtained. Analysis: S, 15.00, 15.10%. Se, chlorine, the halogen atom being split out in the 55 process and, therefore, not characterizing the product.

While there have been described above certain preferred embodiments of the invention, the same is not limited thereto but only by the appended claims wherein it is intended to set forth all features of patentable novelty residing in the invention.

What I claim is:

1. A method of preparing 2-selenyl aryl thiazoles which comprises reacting a selenide with a 2-ha1ogen-substituted aryl thiazole.

2. A method of preparing 2-selenyl aryl thiazoles which comprises reacting a selenide with a Z-chIQrine-substituted aryl thiazole.

3. A method of preparing a 2-selenyl benzothiazole which comprises reacting a selenide with a Z-chIQrine-substituted benzothiazole.

4. A method of preparing a Z-selenyl aryl thiazole which comprises reacting a hydroselenide with a halogen-substituted aryl thiazole.

. 5. A method of preparing a 2 -selenyl aryl thiazole which comprises reacting a polyselenide with a Z-halogen-substituted aryl thiazole.

- azoles which comprises reacting a selenide with a 2-halogen-substituted aryl thiazole under new oxidizing conditions.

. 10. A method of preparing 2-se1enyl aryl thiazoles which comprises reacting a selenide with a 2-ha1ogen-substituted aryl thiazole in an atmosphere of hydrogen.

R. SPERBERG. 

